At present, the IP address in the transmission control protocol/internet protocol (TCP/IP) widely applied in internet has dual functions, that is, serves both as a locator of a host network interface of a communication terminal of the network layer in a network topology, and as an identification identifier of a host network interface of the transport layer. A case of host movement is not taken into account at the beginning of design of TCP/IP. However, the defect of semantics overload of IP address has become increasingly evident with the daily widespread of the hose movement. When the IP address of a host changes, not only the routing will change, but also the identification identifier of the communication terminal host will change, which thus cause more and more routing load, meanwhile the change of host identifier will cause an interruption of application and connection.
The purpose of proposing the separation of the identification identifier and the locator is to solve problems such as semantics overload of IP address and heavy routing load and security, and separate the double functions of IP address, thereby realizing supporting the functions of mobility, multi-home, IP address dynamic redistribution, reducing routing load and exchange visit between different network areas in the next generation of internet, and so on.
In an identification identifier locator separation network, for an initial data packet of user data, because the Access Support Node (ASN) has not yet obtained the mapping information of identification identifier and locator of the destination terminal, therefore the locator of the destination terminal can not be queried locally, and a direct forwarding can not be implemented. There exist two main ideas for solving this problem, one of which is to cache the data packet for which the mapping information can not be queried out locally in the ASN, and not forward it until the mapping information is obtained; the other one is to deliver the data packet for which the mapping information can not be queried out locally to the mapping forwarding plane for forwarding, which is only a conceived thought now and has no specific implementations yet.